Influence of axial load on the stabilities and non-linear dynamic behaviour of thin-walled open section elements
Eulher C. Carvalho1; Paulo B. Gonçalves2; Renzo C. Mancilla2
1 Federal Institute of Education, Science and Technology of Goiás, IFG; 2 Pontifical Catholic University of Rio de Janeiro, PUC-Rio
doi:10.20906/CPS/COB-2015-1048
Resumo
The improvement of the manufacturing processes have led to lighter, stronger and slender structural elements, increasing the importance of researches in this field to ensure that their design is safe under different load conditions. Here, the non-linear dynamic vibrations of a simple supported one-dimensional thin-walled element with open section are investigated. Special attentions is given to the influence of the axial load on the bifurcations and instabilities of the element. For this, a model based on the modified Vlasov's theory is adopted, were warping, shortening and flexural-torsional coupling effects are taken into account, as well as, inertial and geometric non-linarites. By using several tools of non-linear dynamics, a complex dynamic behaviour is observed, principally near to the 1:1 internal resonance region. The results show that the axial load changes the non-linear behaviour of the element from hardening to softening. In addition, bifurcation leading to multiple coexisting solutions are observed.
Palavras-chave: Nonlinear vibrations; Thin-walled section; Open section; Axial load